The use of suction devices to remove body fluids from a wound is known to the art. Such devices are employed to reduce or remove the body fluids which normally collect at a wound site after surgery.
Body fluids which collect as a wound, if left to remain especially in a closed wound, may cause complications in the healing process and thereby reduce the chance of a successful convalescence. Moreover, not only will a dry wound area accelerate the healing stage but will also promote cicatrization.
Known typical suction devices are both disclosed and illustrated in U.S. Pat. No. 3,809,086 to Schachet et al.; U.S. Pat. No. 3,845,765 to Ikeda; U.S. Pat. No. 3,889,677 to Nehring; U.S. Pat. No. 4,058,123 to May; U.S. Pat. No. 4,085,751 to Dodge; and U.S. Pat. No. 4,112,947 to Nehring.
The Schachet et al. patent is directed to a wound suction device including a vessel having therein an elastic sheet diaphragm which is sealed to the walls of the vessel. Movement of the diaphragm by a plate with an actuating means decreases the volume of the vessel which results in the creation of a suction force upon release of the actuating means. Provision is made to lock the actuator means in a position such that the resilient diaphragm remains displaced.
The device disclosed in the Ikeda patent includes a rigid outer vessel accommodating a flexible bag within. The interior of the flexible bag is in communication with the interior of the outer vessel whereby the interior of the flexible bag can be evacuated without its collapse as a result of the equalization of pressure within and without the bag.
The self-contained fluid evacuator of the Nehring '677 patent includes a substantially rigid container with an inflatable member therein. A means mounted on the container is provided for inflating the inflatable member. A valve means responsive to pressure differences between the inflation means and the inflatable member permits a higher rate of fluid flow into the inflatable member than without.
The May '123 and Nehring '947 patents disclose a combined irrigator and evacuator for bathing a wound with an irrigating solution and for removal of fluid therefrom. The apparatus comprises a rigid housing forming a chamber, a biased means dividing the chamber into two sections, a sealing means to prevent fluid flow between the sections, and access means to each section. Depression of the dividing means against its bias produces an increased volume in the irrigating section. Release of the solution from the irrigating section permits the dividing means under bias to return to its original position. During operation, the biasing means pumps fluid from the irrigation section to the wound thereby expanding the evacuation section to create a negative pressure and cause fluid flow therein. A selective rate control flow means provides for simultaneous expulsion of solution from the irrigation section and the admission of fluid from the wound into the evacuation section. Preferably th dividing means is a resilient diaphragm.
The Dodge patent discloses a drainage apparatus including a fluid drainage collection chamber with a liquid seal chamber disposed therein and above the collection chamber. An opening in the upper wall of the liquid seal chamber provides fluid communication between the two chambers. Fluid from the wound passes into the liquid seal chamber which has an initial quantity of fluid and evantually overflows from that chamber into the drainage collection chamber.
Although each of the above-mentioned patented devices is useful in varying degrees, they all suffer from disadvantages to some degree. The body fluids which are collected in typical suction devices sometimes contain a large number of viruses and other pathogenic microorganisms. Persons handling such drainage devices during collection and disposal of body fluids are thus exposed to a high risk of infection during use. Such exposure of the user to infection exists in the Schachet and Nehring '677 patents which disclose removal of the body fluids after collection.
Additionally, suction drainage devices wherein the suction means can communicate with the ambient and also with the collection chamber permit possible contamination of the wound by entry of bacteria and the like along the suction-evacuation flow. The Ikeda and Dodge patents both disclose devices wherein communication between the suction means and the collection chamber is possible thus permitting contamination of the wound.
Moreover, some typical known suction devices possess either complicated or specially required structure which not only increases the cost of construction but also makes operation difficult. The Schachet, May, and Nehring '947 patents disclose multiple-component biasing means. Each of these along with the Nehring '677 patent also disclose a preferred elastomeric member which upon returning to its original form increases the volume of the collection chamber to produce a negative pressure therein. Eventual fatigue of these elastomeric members further decreases the reliability of such devices.
The Ikeda and Dodge patents disclose devices generally limited to upright operation since fluids therein may otherwise gravitationally spill from chambers disposed within.